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<b>DbEnv::set_thread_id_string</b>
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<b><pre>
#include &lt;db_cxx.h&gt;
<p>
int
DbEnv::set_thread_id(char *(*thread_id_string)(DbEnv *dbenv,
    pid_t pid, db_threadid_t tid, char *buf));
</pre></b>
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<b>Description: DbEnv::set_thread_id_string</b>
<p>Declare a function that formats a process ID and thread ID identifier
pair for display into a caller-supplied buffer.  The function must
return a reference to the caller-specified buffer.  The
DbEnv::set_thread_id_string method supports the
<a href="../api_cxx/env_set_thread_id.html">DbEnv::set_thread_id</a> method.</p>
<p>The DbEnv::set_thread_id_string method configures operations performed using the specified
<a href="../api_cxx/env_class.html">DbEnv</a> handle, not all operations performed on the underlying
database environment.</p>
<p>The DbEnv::set_thread_id_string method may be called at any time during the life of the
application.</p>
<p>The DbEnv::set_thread_id_string method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>thread_id_string</b><ul compact><li>The <b>thread_id_string</b> parameter is a function which returns a
buffer in which is an identifier pair formatted for display.  The
function takes four arguments:</ul>
<br>
<b><b>dbenv</b></b><ul compact><li>The <b>dbenv</b> parameter is the enclosing database environment
handle, allowing application access to the application-private fields
of that object.</ul>
<b><b>pid</b></b><ul compact><li>The <b>pid</b> argument is a process ID.</ul>
<b><b>tid</b></b><ul compact><li>The <b>tid</b> argument is a thread ID.</ul>
<b><b>buf</b></b><ul compact><li><a name="2"><!--meow--></a>
The <b>buf</b> argument is character array of at least
DB_THREADID_STRLEN bytes in length, into which the identifier
pair should be formatted.</ul>
<br>
<br>
<p>If no <b>thread_id_string</b> function is specified, the default
routine displays the identifier pair as "pid/tid", that is, the process
ID represented as an unsigned integer value, a slash ('/') character,
then the thread ID represented as an unsigned integer value.</p>
<br><b>Errors</b>
<p>The DbEnv::set_thread_id_string method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>An
invalid flag value or parameter was specified.</ul>
<br>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>
<br><b>See Also</b>
<a href="../api_cxx/env_list.html">Database Environments and Related Methods</a>
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